Cork still king, but wine taste is what matters

July 26, 2007

PORTLAND, Ore. — Despite the increasing use of metal screwcaps to seal bottles of fine wine and protect their contents from the moldy cardboard flavor brought on by fungal contamination – also know as “cork taint” – the public hasn’t yet bought in to the technology.

Screwcap closures for wine remain largely unpopular with consumers, but new research from Oregon State University suggests that all is not lost.

Winemakers who provide more wine tastings and increase consumers’ exposure to alternative closures are helping them understand that a fine pinot noir or Chardonnay sealed with a screwcap can be equal in quality and worth the same price as wine closed with traditional natural cork.

“We have found that an individual’s liking for the way a wine tastes can override bias associated with a the type of closure used on the bottle, when deciding whether to buy a wine,” said Anna Marin, an associate professor in Oregon State University’s College of Agricultural Sciences.

“Increased exposure to the screwcaps through winery-organized tastings and events that give consumers a chance to try the wine may assist in bettering the image of screwcaps.”

In the United States, wine drinkers remain predisposed to natural cork despite research results indicating an inability to detect a difference in the taste, smell, appearance or “mouth feel” among bottles of Chardonnay and merlot closed with synthetic cork, natural cork or metal screwcaps, said Marin.

To determine the level at which knowledge of the closure type affected perceptions of quality and cost, OSU researchers enlisted a panel of tasters to rate two wines twice; first without knowing how the bottles were sealed, then with the closure information in front of them.

During the first tasting of a Chardonnay and a merlot, the subjects were given no information that could affect judgment of quality, such as type of wine or variety, label information including brand, price and closure type, said Marin, who conducts research at OSU’s Food Innovation Center in Portland.

“In the second tasting, the only additional information given to the tasters was about the type of closure on the bottle,” she said. “This information alone affected the testers' perception of the wine quality.”

The researchers also found that consumers expected to pay less for a bottle of wine with a screwcap because they believed the wine to be of lower quality. However, the greatest impact on whether or not a consumer would purchase a wine was the degree to which they liked the taste.

“Ultimately people will purchase a wine that they know they will enjoy,” said Marin.

The research appeared in the summer issue of the American Journal of Enology and Viticulture.